Our research program develops and applies methods of genetic epidemiology, especially segregation analysis of major loci and continuous variation, path analysis of cultural and biological determinants of family resemblance, computer assistance for genetic counseling, and gene mapping. This supplement is to replace a computer acquired in 1965 which is labor intensive, expensive to maintain, and incapable of multiprogramming and remote job entry, by a modern midi-computer which will be at least five times faster, cheaper to maintain, and labor-conservative through multiple streaming of interactive programs for analysis on site and by remote entry.